Conventional light bulbs are omnidirectional, but their illumination is not intense beyond a short distance. In order to provide a light that would cast its illumination over greater distances, inventors developed flashlights and spotlights. These devices focus the light beam so that it travels over greater distances, but the omnidirectionality of the light is lost.
Accordingly, a number of inventors developed light fixtures having focused beams that would spin about an axis at a high rate of speed. These fast spinning lights were the first to provide omnidirectional lighting beyond the capabilities of a fixed position light source, but the mechanical forces acting upon the bulbs shortened the lifetime of such spinning bulbs and made them unacceptable.
In 1977, Du Shane was awarded U.S. Pat. No. 4,054,791 for a portable lantern having a high speed rotary beam. A mirror was mounted at a forty five degree angle relative to the vertical and spun at high speeds. The result was a fast-spinning spotlight beam that provided an intense omnidirectional light.
It has been determined, however, that a rapidly rotating mirror positioned at a forty five degree angle is subject to rotational problems because of the inherent instability of a flat, planar article mounted at a forty five degree angle. Thus, at high speeds of rotation, vibration appears and greater rotational speeds cannot be obtained.
Thus, there is a need for an omnidirectional light that is not subject to vibration-related problems, but the prior art neither teaches nor suggests how such an instrument could be provided.